Abstract Complete expressions for wind momentum and energy transfer to wind-generated waves are derived based on a boundary-layer integral method. The airflow and wave measurements as made by Wu et al. (1977, 1979) are used to provide a first-order estimate of the momentum and energy budget. The momentum and energy transfer to waves are found to be dominated by the wave-induced pressure and mainly received by the dominant wave, which agree with the wind energy input mechanism of a nonlinear wind-waves model proposed by Lake and Yuen (1978) and Yuen and Lake (1979). It is found that the waves support about 61% of the total wind momentum, but receive only about 29% of the tow wind energy across the interface. This low fraction of energy to the waves is found to be the consequence of a high ratio of mean surface current velocity to wave celerity which results in a considerable leakage of energy delivered by the wave-supported momentum to the current. The measured energy transfer to waves by the wave-induced ...